msm: ipa: interface to provide pdn configuration

Make interface changes to get PDN configuration. The ioctl
can be used to notify whether a PDN is in IP collision
mode or in IP passthrough mode and provide the required configuration
information.

Change-Id: I13a7c28bad2702a933e80428d54745a86a4c62ec
Signed-off-by: Chaitanya Pratapa <cpratapa@codeaurora.org>